The present disclosure generally relates to self-piercing rivets as well as to strap systems which are used in packaging.
Cardboard cube frames are sometimes used to package items in a way that they can be readily exhibited at the point of sale. One such cardboard cube frame is disclosed in U.S. Patent Publication No. 2006/0131371 A1. The frame consists of a plurality of edge pieces which are held together by fixating devices. A plastic film is then wrapped around the frame to help secure the product in the frame. The film is kept in place while the package is transported, but then is removed at the point of sale for product exhibition.
Instead of using plastic film, fixed-length straps are sometimes used. In such a case, there is a strap handle provided at each end of the strap, and each strap handle is engaged with a fastener which is secured to the outside of the frame. The manufacturing tolerances of the frame often cause a fixed length strap to be loose when installed. If the fixed length strap is not too loose, then a tool is typically required to stretch the strap handle over the fastener.
To provide enhanced stability to the frame, thin sheet metal or cardboard corner pieces may be used within the corners of the frame. In such a case, the relatively thick cardboard edge pieces must be fastened to the corner pieces somehow. This is typically done by drilling holes through the cardboard edge pieces and the corner pieces, and then installing fasteners in the holes. This process is time-consuming and difficult to perform in an automated process.